1 files changed, 2 insertions, 2 deletions
diff --git a/cli/js/40_jupyter.js b/cli/js/40_jupyter.js
index 9fab1c414..0e0a4d7ac 100644
--- a/cli/js/40_jupyter.js
+++ b/cli/js/40_jupyter.js
@@ -342,7 +342,7 @@ function enableJupyter() {
   async function broadcast(
     msgType,
     content,
-    { metadata = {}, buffers = [] } = {},
+    { metadata = { __proto__: null }, buffers = [] } = { __proto__: null },
   ) {
     await op_jupyter_broadcast(msgType, content, metadata, buffers);
   }
@@ -400,7 +400,7 @@ function enableJupyter() {
     if (options.update) {
       messageType = "update_display_data";
     }
-    let transient = {};
+    let transient = { __proto__: null };
     if (options.display_id) {
       transient = { display_id: options.display_id };
     }